Press 1 for knock-knock jokes.

Dedicated in 1895, this is the world's first tribute to the hardworking newspaper delivery boy.

You can get anything you want at the former site of the restaurant immortalized by Arlo Guthrie.

Take a step inside the picturesque studio of America’s most renowned sculptor.

Herman Melville wrote 'Moby Dick' in this landmark 18th-century house surrounded by farmland.

The revival of a classic Art Deco theater.

An FDR-era tuberculosis sanatorium has stood abandoned in the suburbs of the U.S. capital for over 30 years.

These five Art Deco homes were meant to solve the "small house problem."

The only Civil War battle in Washington D.C. took place near this highest natural point in the city.

A Civil War fort in the middle of Washington, D.C. has been swallowed by a forest.

A tribute to the beloved, kind-hearted "homeless mayor" of Silver Spring.

An old pay phone rewired to play local bird calls and songs at the press of a button.

An Industrial Revolution-era public work that purified water using nothing but sand.

This American Civil War-era fort still stands near the border between Washington, D.C. and Maryland.

An outlandish shoe shaped house built by an eccentric millionaire.

In this cemetery stands the country's first public crematorium.

The home of possibly the least-loved U.S. president stands as a sort of unpopular Monticello.

The first of Lancaster's "rural cemeteries."

This iconic Lancaster everyman has been reading the same story since 1980.

The oldest farmer's market in America is so ancient it was approved by the King of England.

This groundbreaking 16th-century map is known as "America's birth certificate."

One of the three perfect vellum copies of this historic book known to exist is on display in a specially-designed case.

This statue of one of baseball’s greatest pitchers looks like something out of a sci-fi horror movie.

Outside the Department of Transportation, a collection of artifacts honors the history of how we get around.